1. Field of the Invention
The present invention relates to an inside and outside air switching apparatus for an automotive air-conditioner.
2. Description of Related Art
In a conventional inside and outside air switching apparatus for an automotive air conditioner, as shown in FIG. 7, there is a flat door system where a flat filter 9 is disposed at right angle to an air flowing from an inside air inlet 72 and an outside air inlet 71 to an inlet port 102 and the inside air inlet 72 and the outside air inlet 71 are open and closed by a rotation of a flat door 8.
In another conventional apparatus, as disclosed in U.S. Pat. No. 5,391,112, a filter formed in an arcuate shape is disposed in a rotary door.
In the above-mentioned conventional inside and outside air switching apparatus for an automotive air conditioner using the flat door system, when the flat filter 9 is disposed in an air duct, the flat filter 9 needs to be positioned lower than the operating space of the flat door 8 to keep the flat door 8 being operated smoothly. As a result, the distance between the flat door 8 and the flat filter 9 is enlarged, thereby making the size of the inside and outside air switching apparatus larger.
To overcome the above problem, as shown in U.S. Pat. No. 5,391,112, by using an arcuate rotary door and disposing a filter in the rotary door, the size of the inside and outside air switching apparatus for automotive air conditioner can be made smaller as compared to the switching apparatus using the flat door.
However, in the inside and outside air switching apparatus for an automotive air-conditioner using the rotary door, since upper and lower cases need to be disassembled when cleaning or exchanging a filter, there is a problem in that the apparatus has an disadvantage of the working efficiency for cleaning and exchanging the filter.